Material amd process of using the



Patented Sept. 12, 1939 PATENT OFFICE MATERIAL AND PROCESS OF USING THESAME IN THE LIETAL WORKING ART Michael W. Freeman, Detroit, Mich.

No Drawing. Application May 27, 1935,

Serial No. 23,705

10 Claims.

The present invention relates to a material and to the process of usingthe same in the metal working arts for forming, processing, handling,and finishing of metal.

In the metal working arts, it is quite customary to take a piece ofmetal, for example, a fiat sheet, bar, or wire, and to subject it to oneor more successive rolling, stamping, drawing, or cold forgingoperations to transform the metal blank into an article of predeterminedconfiguration and dimensions. To perform these operations satisfactorilyand economically, it is necessary to give consideration to the effect onthe metal being worked upon and the dies or other instrumentalities usedin working-the metal.

Often the final article produced is formed by welding or otherwiseuniting two or more parts together. Usually the shaped article isfinished by the application of a coat or coats of paint,

0 metal platings, rubber, or the like. Heretofore,

it has been the custom to employ a lubricant during the shaping orworking operations; a flux when welding; special preparations whenplating or painting, and so on; and frequently, if not always, thetreatment'for one stage of operation is antagonistic to subsequentstages, necessitating cleaning or washing of the metal object betweenstages.

By way of example, it is mentioned that in the drawing of metal,so-called drawing compounds, which are in reality lubricants, areapplied to produce a film between the metal and the die for protectingthe die from excessive wear, thus preserving its .design and life ofutility. Not only is it important to protect the die, but it is likewiseimportant to work the metal in a way that its structure is not adverselydisturbed and not requiring excessive cleaning or other work thereon asa direct result of the rolling, drawing,

stamping, or other operations.

Dies in most instances are quite expensive, requiring skilled labor intheir production, and are necessarily of accurate dimensions. Inselecting a lubricant for use between a die and metal to be 46 shaped,the lubricant or drawing compound should have excellent coveringproperties, particularly capable of resisting the squeezing out actionpromoted when the die and work are pressed together and to also resistsegregation.

50 Further, the ideal properties of a lubricant or drawing compound aresuch as not. to interfere with subsequent operations on or treatment ofthe metal.

Ordinarily, a drawing compound is used for its effectiveness only duringthe drawing operation,

and by reason of necessity it is the practice to remove the remains ofthe drawing compound after the metal working steps. An importantadvantage gained by the use of my material resides in the fact that thesame material, and in 5 many cases a single application thereof, willserve in various capacities. That is, the material in some cases can beapplied initially as a drawing lubricant by way ofexample, and left onthe work so that after drawing it may serve 10 as a base for weldingand/or as a means to facilitate adhesion of a protective or decorativecoating such as rubber, paint, or other finishes to the metal surface.

One of the primary objects of the invention is 15 to provide a materialor composition and method of using the same wherein it will serve as adrawing lubricant more efficiently than present conventional lubricantsfor the same purpose and will at the same time in some cases serve other20 purposes and eliminate some stages of operations. This will beexplained more in detail hereinafter.

The expressions drawing compound, composition, and material as usedthroughout the application will beunderstood to include a lubri- 25 cantfor rolling, drawing, shearing, piercing, stamping, cold forging, andother operations in the metal working arts for forming, processing,handling, and finishing metals, and to also serve as a base for weldingor as a means to facilitate adhesion of protective .coatings such asrubber, paints, metal platings, and the like.

The main object of the invention is to produce a material or compositionof this character in the broad sense as stated above made from or 35including organic sulphonic acids or mixtures thereof, their salts, ortheir derivatives, and is in no way limited to any particular method ofobtaining these compounds.

Broadly speaking, the organic sulphonic acids and their salts can beroughly divided into two groups, namely: (1) the aromatic hydrocarbons;and (2) the aliphatic hydrocarbons. This invention contemplates the useof both the sulphonic acids and their salts of both the aliphatic andaromatic hydrocarbons and also the derivatives of the organic sulphonicacids and their salts of both the aromatic and aliphatic series ofhydrocarbons.

Taking into consideration the matter of cost of materials on the markettoday, it is desirable to use sulphonic acids or salts or derivativesthereof of the aromatic hydrocarbon series, although sulphonic acids,their salts, or derivatives from 55 the aliphatic series can and havebeen used by me with very satisfactory results.

As examples of organic sulphonic acids or derivatives thereof, thefollowing may be mentioned:

Hexane sulphonic acid,

Amyl sulphonic acid,

Mono chloro amyl sulphonic acid, Benzene sulphonic acid,

Phenol sulphonic acid, Naphthalene sulphonic acid, Heptane sulphonicacid,

Acetone disulphonic acid, Dichloro amylene sulphonic acid, Myristicsulphonic acid,

Stearic sulphonic acid, Anthracene sulphonic acid,

The sulphonic chlorides, Disulphonic dinaphthyl methane, Tristearinsulphonic acid, Amylum sulphonic acid, Spermaceti sulphonic acid.

As a further example to show one method of producing a satisfactorymaterial, commercial benzol, which may contain toluene, xylol, phenol,and other compounds, can be treated in the following manner:

The commercial benzol is sulphonated with fuming or concentratedsulphuric acid, the mixture being subjected to elevated temperatures.Starting with a definite weight of concentrated or fuming sulphuricacid, say 100 mole weight, heated gradually, commercial benzol is addedeither in the liquid or vapor state to the extent of about 50 to '75mole weight until approximately from one-half-to three-fourths ofsulphuric acid is reacted with the benzene to form benzene sulphonicacid and-a mixture ofother sulphonic acids. To the sulphuric acidbenzene sulphonic acid mixture commercial naphthalene is added untilabout 50% of the remaining free sulphuric acid reacts with it to formnaphthalene sulphonic acid.

In one production factory test run, the crude naphthalene employed inthe above mixture was approximately 50% naphthalene, 20% phenanthrene,10% carbazole, and 20% anthracene. To this was added about 4 mole weightof phosphorus pentaoxide to take up the water of reaction, and withcontinued heating the resultant composition of sulphonic acids wassubstantially free from sulphuric acid.

Inpassing, it may be stated that the chloro benzene, chloro naphthalene,stearin, spermaceti, stearic acid, and the like were used in a mannersimilar to that just described with extremely satisfactory results forwire drawing operations.

The necessity for providing a drawing compound free from sulphuric acidwill vary depending upon the application. In some cases, relativelylarge amounts of free sulphuric acid may be tolerated withoutdetrimental effect, while in other cases the content of free sulphuricacid should be reduced to a minimum. I prefer to keep the drawingcompound free from sulphuric acid to avoid any risk of undesirableattack upon either the metal being worked upon or the work- 4 inginstrumentalities.

The composition produced in accordance with the above instructions wasthen dissolved in water to produce a solution which was applied to themetal and preferably the temperature of the bath is elevated duringtreatment of the metal.

To test the efficacy of the material for various applications andprocesses, many factory prothe rods treated in the sulphonic acidmixture solution were welded with the area of weld being smooth andgenerally much more satisfactory in appearance than was the case withthose rods welded without the treatment. The comparison was carriedfurther than that of appearance by separating the rods where welded andpolishing them for .micro inspection. This inspection showed that therods treated with the sulphonic acid material appear to receive the welduniformly, while the untreated rods had spots separating the weld fromthe surface of the metal, indicating that the sulphonic acid mixtureimproved the weld between the rod sections as well as the appearance ofthe welded pieces.

Instead of subjecting the metal piece to be welded to treatment, thewelding wire may be treated either with a sulphonic acid only or with acomposition binding material containing the sulphonic acid as its activeconstituent. In other words, the tests show that all that is necessaryfor satisfactory welding is to have the sulphonic acid, mixturesthereof, salts, or derivatives thereof, present during the weldingoperation. Sheet steel and heavy steel plates have been welded in thesame way with equally satisfactory results.

(2) To show the effect of my material on the adhesion of paint andrubber to metal treated therewith, some metal pieces were firstsubjected applied. This was evidenced by the humidity and salt spraytest.

For a period of about one year, production tests were carried out in alarge enameling plant, and it was conclusively found that the metalsurfaces treated with my composition were enameled in a manner muchsuperior to those pieces enameled without this treatment. Further tests'on the impact machine also proved that it surpassed conventionalenameling.

(3) To show the effects of the sulphonic acid material on plating, aproduction test was conducted with metal parts prepared in theconventionalmanner by first treating the metal parts with a solutionincluding a sulphonic acid and the pieces were then plated with acadmium plating, and it was observed that the cadmium coating was muchmore uniform and adherent than without the use of the sulphonic acidfilm when subjected to the salt spray test. It may be noted that in somecases it is possible that the metallic salts, such as chromium, nickel,and the like, of the sulphonic acids may be used as plating materialshould it be more convenient to do so in lieu of applying the film onthe finished articles. (4) As to the properties of a sulphonic acidmaterial when using the same in drawing, rolling, stamping, shearing,and similar operations, production tests were conducted in severaldifsurrounding'atmosphere on the film as well as ferent large steel,automobile, and other plants. These tests are of course onlyrepresentative, applications, as those versed in the art will readilyappreciate the applicability of the. material to. many other uses notspecifically hereinset forth. For example, in one of many runs, innerflanges,

to be made from 11 gauge hotroll steel from strips about l2"x84"x/;;",,were placed in a bath composed of about 90% water and 10% of thetime for treatmentis suflicient whenthe metal attains the temperature ofthe bath, which ordinarily is in the neighborhood of 200 degrees theeffect on the metal which in this case hapsubjected to four difierentoperations.

of burring could be'eliminated. The above op erations are referred to asdry stamping, and.

after stamping about thirty-five tons of the 11 gauge steel, itwas'discovered that the dies were actually in better condition thanbefore they were used for shaping the metal coated with film ofmymaterial.

This would suggest that the steel may be treated at the steel mill withmaterial in accordance with my invention, and then sent out ready fordrawing and stamping to the fabricator. Similarly, such a film can beleft on drawn wire for shipping. to the cold forging or welding plantswithout further treatment required.

(5) In another application, sheets are rolled from one-half inch bars,which are cut to proper length depending on finished sheet to beproduced. The bars are heated until they become red hot and are thenrolled a number of times until their thickness is about twice thethickness of the ultimate thickness desired. It is then customary topickle the metal, after which it is again heated to red heat and to thenroll the breakdown sheets in pairs that is, one upon the other.oftentimes this results in a sticking or rolling together of the sheets.

I overcome this difliculty by coating the breaka down sheets to berolled together with my sul phonic acid material which may, if desired,include, in addition to the iron salts of sulphonic acid, such salts asaluminum, magnesium, lead,

etc. of the sulphonic acid. Then when the coated metal pieces are made"red hot for rolling in pairs, the coating material is converted into acarbonaceous residue or soot, giving a powdery coating or layer capableof resisting welding or undue sticking of the sheets together.

One of the decided advantages gained when using my material orcomposition is that when the metal is treated with it, it can ordinarilybe passed through successive metal working stages without the necessityof applying other drawing compounds or conventional lubricants betweendifferent operations. In drawing wire, for example, thec oils may betreated in a bath of my material. This material may include highmolecular weight fatty acids, their salts, such as stearic, palmitic,etc., their glycerides and esters ,and'their sulphonic acids or'salts.No further washing or liming, or application, of. other draw- :ingcompound, is necessary. The coils of wire .treatedinthismanner werefurther drawn and subsequentlysubjected'to cold forging withoutfurther}. treatment. This of .course depends somewhat upon the specificoperations through the sulphonic acid mixture for a period of severa]minutes; When ;it is not necessary to remove mill or oxide scale fromthe metal surfaces,

which jthefwire is passed and in some cases-it may beadvisable'to-recoat. the wire with additional material. I

As examples of other work done, but which in K101591156 constitutes acomplete statement of the uses'towhich this compositionhas and can beput; -7 gauge metal was passed through three successive operations toproduce brake drums. ,11 gauge metal for spare wheel carrier boltflanges] was blanked and drawn, restruck and sized, and pierced. Fendersupports of 11 gauge -'.material were blanked, formed, and pierced, withimilar operations beingused for producing running board supports made of11 gauge steel.

Emergency brake drums were made from 9' gauge {steel with two andone-half inch surface in a single draw, blanked, drawn, restripped,trimmed,

"rid pierced. 's The art of metal working is so diversified that t isnot feasible to attempt to prescribe specific ,combinations of sulphoniccompounds and instructions for any and all conditions. Therefore,representative. examples are herein set forth which will clearlydisclose to the art various uses and then store the treated metal fora.ong period of time, or to ship it over a long distance before finaldeformation or shaping of the metal. Under these circumstances, it issuggested that a sulphonic acid, substantially water insoluble at normaltemperatures, be incorporated, such as, for example, hexadecyl sulphonicacid and the like which are very sparingly soluble in water below 50degrees centigrade.

Where continuous drawing is employed, such as in wire drawing, the diesget heated up often to temperatures of about 90 degrees, centigrade, andsometimes in excess of this temperature. In such cases, it is usuallyfound to be advantageous to incorporate a sulphonic acid or derivativethereof of higher boiling point and capable of solidifying more readily.The salts of such sulphonic acids have a high melting point and permit amore efiicient and uniform draw. In such cases, I have incorporated amixture of sulphonic acids as above described and stearic sulphonicacid, its salts, or the like.

In other cases and particularly in some forms of stamping and drawingwhere the impact and distribution of stresses are not uniform, it isdesirable to incorporate other materials that are capable of maintainingthe salts of the sulphonic acids in a plastic state after the water hasevaporated. In such cases, I have added chlorinated materials andpreferably those chlorinated mate: rials that do not decompose easily atelevated temperatures, or other plasticizers and liquids, such astrichlorphenol oxide, dibutyl phthalate, and the like, with possibleadditions of pyridine, quinoline, or isoquinoline, as well as otheractive amines of the aliphatic series. The amines have 7 the property ofreducing the effect of mobility of the chlorine radical and the like,thereby increasing materially its rust-proof properties. In someinstances, I have found it possible to add conventicnal lubricants anddrawing compounds.

'Other advantages to be gained by the use of my material are that thedies have a longer life than with prior art lubricants, notwithstandingthe fact that in some cases they may become heated more easily with thisdry drawing process. Ordinarily, the heat thus generated is not objectionabe but in those cases where it is, a small amount of suitablefluid may be periodically placed upon those areas of the die showing atendency to overheating. My material spreads more uniformly, thusallowing the use of a batch system and centralized control particularlyin the larger plants. A further important advantage is that the materialpossesses the. property of cleaning the surfaces of the metal at thesame time the drawing material is applied; that is, during the time themetal is in the solution, it is cleaned, the extent of cleaningdepending upon the concentration of the bath, the temperature thereof,the length of time the metal is left in the bath, the type of metal, andother variables.

It will be understood that the sulphonic acid, saits, or derivativesthereof, need not be used in solution form, although ordinarily this ispreferable, because in drawing wire, for example, which has previouslyhad scale removed so that it is clean, the wire may be drawn through drysulphonic acids or salts thereof. In other words, the wire passing tothe die may be moved through a body of powder or crystals of thesulphonic acid.

Bright stock may be produced by passing the wire through a "liquidsulphonic acid, its salts or derivatives, or a solution thereof.

I claim:

1. In the metal working art, the method of preparing metal forfabrication including the step of subjecting the surface of said metalto 'a solution having as its principal active constituent an organicsulphonic acid substantially devoid of mineral acid content.

2. In the metal working art, the method of preparing metal forfabrication including the step of subjecting the surface of said metalto a solution having as its principal active constituent salts of theprincipal active constituent of which is an organic sulphonic acidsubstantially devoid of mineral acid content.

4. In the metal working art, a method including the step of fabricatingmetal in the presence of a material the principal active constituent ofwhich is an organic sulphonic acid substantially devoid of mineral acidcontent.

5. In the metal working art, the method of working a plurality of piecesof metal simultaneously in contact with one another including the stepof interposing a material the principal active constituent of which isan organic sulphonic acid substantially devoid of mineral acid content.

6. In the metal working art, the method of joining pieces of metaltogether including the step of subjecting the contacting surfaces ofsaid metal pieces to a material the principal active constituent ofwhich is an organic sulphonic acid substantially devoid of mineral acidcontent.

7. In the metal working art, the method of drawing metal including thestep of coating the surface of the metal to be drawn with a material theprincipal active constituent of which is an organic sulphonic acidsubstantially devoid of mineral acid content.

8. In the metal working art, the method of drawing metal including thestep of coating the surface of the metal to be drawn with a material theprincipal active constituent of which is an organic sulphonic acidsubstantially devoid of mineral acid content, said material including analkaloid.

9. In the metal working art, the method of preparing a metal surface foroperations thereupon including the step of coating the same with anorganic sulphonic acid substantially devoid of other activeconstituents.

10. In the metal working art, a material for treating metal surfacescomprising a sulphonic acid substantially devoid of other activeconstituents.

MICHAEL W. FREEMAN.

